Triple wall chimney pipe assembly

ABSTRACT

A prefabricated pipe assembly for use in forming a chimney is made up of outer, intermediate, and inner pipe sections which define spaced apart walls. Groups of projections are formed on the inner periphery of the outer section for maintaining the intermediate section concentrically positioned therein. Spacer ring structure is mounted within the ends of the outer section to hold the intermediate section longitudinally therein and concentrically position the inner section. Cooperating structure is formed on the inner section and spacer rings to hold the inner section longitudinally in place. Interlocking male and female structure is formed on opposite ends of the pipe assembly for joining one with another.

I United States Patent 1191 1111 3,872,780 Zanias Mar. 25, 1975 TRIPLEWALL CHIMNEY PIPE ASSEMBLY [75] Inventor: Theodore Zanias, Anaheim,Calif. l Examu 1er wflham O D ea Assistant Examiner-Peter D. Ferguson[73] Assignee: American Metal Products Attorney, Agent, or Firm-Herzig &Walsh Corporation, Los Angeles, Calif.

[22] Filed: Apr. 3, 1974 57 ABSTRACT [2]] Appl' 457,606 A prefabricatedpipe assembly for use in forming a chimney is made up of outer,intermediaate, and inner [52 us. c1 98/60, 126/307 R, 138/113, p pSections which define spaced apart walls- Groups 13 114 235 133 R, 235133 of projections are formed on the inner periphery of 51 1m. (:1 E04h17/02 the Outer section for maintaining the interniediate [58] Field ofSea h U 93/58 60; 126/307 R 312; tion concentrically positioned therein.Spacer ring 133/113 114; 235/47 133 R, 133; 110 1 4 structure is mountedwithin the ends of the outer sec- 3 tion to hold the intermediatesection longitudinally [5 References Ci d therein'and concentricallyposition the inner section. UNITED STATES PATENTS Cooperating structureis formed on the inner section 2 7S 2 and spacer rings to hold the innersection longitudii i et a1 g nally in place. Interlocking male andfemale structure 22916308 10/1959 62,5?:JJJJJ'"'"TJJJJJJJJJJJJJ: mm isformed 99911305116 ends of the Pipe assembly for 2.947303 8/1960 EpsteinJ'Oimng one wlth another- 2,962,053 11/1960 Epstein..... 2,976,7973/1961 Newbill l26/307 R 13 Clams 7 Draw PATENIED HARE 5 I975 SHEET 2 UF2 BACKGROUND OF THE INVENTION Patent Date No. Patented Inventor9,634,720 14 April I953 R. K. Thulman 2,650,112 25 August I953 A.Kinkead 2.650.l I4 25 August I953 -S. Epstein 2,910,308 27 October 1959J. H. Carr 2.936,l84 l May 1960 S. Epstein 22,947,303 2 August I960 S.Epstein *2.962,053 29 November I960 S. Epstein SUMMARY OF THE INVENTIONIt is an object of the present invention to provide'a chimney pipeassembly of the triple walltype which is an improvement over the priorart and is characterized by having one or more of the followingadvantages:

a. Capable of providing a safe and durable passage for hot flue gaseswhich does not buckle and effectively distributes heat, thereby to avoidthe formation of dangeroushot spots on its wall portions;

b. Capable ofbeing prefabricated by low cost mass production methods andhaving rapidly reproducible parts which are easily and readily assembledso as to minimize labor costs;

c. Capable'of being constructed with a relatively small cross-sectionalsize while still meeting safety requirements, thereby to permitreductions in installation space required, shipping weight, and storagespace;

d. Having its inner,'intermediate and outer walls held in an accuratelyspaced apart relationship so as to insure required clearances to meetsafety and efficiency standards;

e. Constructed to permit limited movement between assembled parts toprevent buckling caused by thermal expansion and contraction; and

f. Suitable for use with a variety of fuels including oil, wood, coal,and others, and in various building structures including domesticresidences.

In accomplishing these and other objects, there is provided inaccordance with the present invention a prefabricated pipe assembly foruse in forming a chimney made up of outer, intermediate, and inner pipesections which define spaced apart walls. Groups of projections areformed on the inner periphery of the outer section for maintaining theintermediate section concentrically positioned therein. Spacer ringstructure is mounted within the ends of the outer section to hold theintermediate section longitudinally therein and concentrically positionthe inner section. Cooperating structure is formed on the inner sectionand spacer rings to hold the inner section longitudinally in place. Theprojections formed on the outer section hold the intermediate pipesection concentric with the inner and outerpipe sections in a loose fitwhich permits thermal expansion and contraction without buckling.Interlocking male and female structure is provided on opposite ends ofthe pipe assembly so that one pipe assembly may be jointed with anotherin order to form a length of chimney.

Additional objects of the present invention reside in the specificconstruction of the chimney pipe assembly shown in several drawingshereinafter described in connection therewith.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation view of apartially assembled chimney made up of pipe assemblies according to thepresent invention, certain of the pipe assemblies being partiallycutaway to illustrate internal construction.

FIG. 2 is a view taken along the line 2-2 of FIG. 1.

FIG. 3 is a view taken along the line 3-3 of FIG. 1, looking upwards.

FIG. 4 is a view taken along the line 4-4 of FIG. 1.

FIG. 5 is a view taken along the line 5-5 of FIG. 1.

FIG. 6 is a view taken along the line 6-6 of FIG. 1.

FIG. 7 is a perspective view of the male and female end portions of theuncoupled pipe section assemblies of FIG. 1, shown partially cut away toillustrate internal construction.

DETAILEDDESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to thedrawings in more detail. there is shown in FIG. 1 a length of chimneymade up three sections of pipe assembly 10; The two uppermost assembliesare illustrated coupled together and are designated 10A and 10B, goingfrom the top downwardly. The lowermost assembly 10C is only partiallyshown and is illustrated positioned for coupling to the lower end of theassembly 108. 1

Each of the pipe assemblies 10 are identically constructed and includean outer pipe section 11, an intermediate pipe section 12 and 'an innerpipe section 13. The pipe sections 11-13 are illustrated as beingcylindrical and may, for example, be made from rectangular plates ofstainless steel by crimping their opposite edges together to formlongitudinal seams 9, as shown in FIG. 3. The pipe sections 11-13 areappropriately dimensioned for concentric positioning within each otherto define spaced apart walls with the intermediate pipe section 12dimensioned for positioning substantially midway between the inner andouter pipe sections 13 and 11.

Each of the pipe assemblies 10 has a male end portion 14 and a femaleend portion IS. The end portions 14 and 15 are illustrated as beingformed as an integral part of the outer pipe sections 11. The female endportion 15 is shown formed by an annular collar of substantially thesame diameter as the outer wall portion defined by pipe section II andhas inwardly extending locking lances or flanges 16 formed thereon. Theflanges-I6 are preferably punched out from the collar portion 15. Thelocking flanges 16 define locking edges 17 which engage outwardlyextending arcuate shaped beads or projections 18 formed around the outerperiphery of the male end portion 14. The projections 18 are illustratedformed in the male end portion 14 by being impressed therein. The maleand female end portions 14 and 15 interfit and interlock, as illustratedin FIGS. 4 and 6, to join one of the pipe assemblies 10 with another.

As shown in FIGS. 2, 5, and 7, a group of inwardly extending projections20 are formed on the inner peripheral surface of the male end portion14. The projections 20 are preferably made by forming indentations inthe outer periphery of the pipe section 11 at intervals equally spacedapart circumferentially. The projections 20 illustrated define a commonplane substantially perpendicular to the longitudinal axis of the pipesection 11. Each of the projections 20 is similarly dimensioned andextends inwardly to form an arc portion 21 which is radially positionedapproximately at the location whereat it is desired to hold and maintainthe intermediate wall portion 12. An appropriate number of projections20 is formed on the pipe section 11 to concentrically support theintermediate pipe section 12 therein.

Rigidly secured to each of the projections 20 is an annular spacer ring22. The spacer ring 22 is connected to the projections 20 by means ofextensions 23 which are illustrated formed integral with the ring 22.The extensions 23 have flange portions 24 formed on their outer endswhich are secured to the projections 20, such as by being spot weldedthereto. The spacer ring 22 and extensions 23 preferably lie in a commonplane. The inner diameter of the spacer ring 22 is greater than theouter diameter of pipe section 13 but a selected distance smaller thanthe inner diameter of the pipe section 12. Thereby,the spacer ring 22does not completely close the end of the intermediate pipe section 12 toallow the 'flow of gas therethrough.

Referring to FIG. 5, the spacer ring 22 is illustrated positioned in aplane substantially perpendicular to the longitudinal axis of the pipesection 11 with the extensions 23 joining the projections 20 atapproximately the points whereat the slope of the projections 20 changefrom the vertical to an outward slope. The upper end of the pipe section12 is positioned just below the planar portion of the ring 22 in a loosefitting relationship within the projections 20. Thereby, space isprovided in which the pipe section 12 may thermally expand or contractwithout buckling.

The inner periphery of the spacer ring 22 is formed to define adownwardly extending annular flange 30. The annular flange 30 isconstructed to have a diameter slightly larger than the outer diameterof the inner pipe section 13 and fits over the outwardlyexpanding-flared upper end 31 of the wall portion 13. Space is therebyprovided for the lower end 32 of the inner pipe section 13 in the upperpipe assembly A to slidably mate within the enlarged end portion 31 ofthe inner section 13 of pipe assembly 108 in sliding contact with theannular flange 30. Thereby, the projections and the annular spacer ring22 cooperate to hold the upper ends of the pipe sections 11, 12, and 13spaced apart in a concentric relationship with respect to each other. Asabove noted, the pipe assemblies 10 illustrated are dimensioned so thatthe intermediate sections 12 lie substantially midway between the outerand inner pipe sections 11 and 13.

A view of the lower female end of the pipe assembly 108 is shown inFIGS. 3 and 7. As there shown, a planar spacer ring 40 is mounted withinthe female end portion 15. The ring 40 itself corresponds in size to thering 22 and has outwardly extending planar extensions 41 thereon. Theextensions 41 correspond in number to the extensions 23 on the ring 22,are similarly shaped, are dimensioned to reach the inner surface ofouter pipe section 11, are equally spaced apart circumferentially, andare positioned in radial alignment with the projections 20 formed on theupper end of the pipe assembly. Formed on the outer end of theextensions 41 are flange portions 42 which extend downwardlyperpendicularly to the plane of the ring 40. The flange portions 42 arerigidly secured preferably by spot welding to the inner periphery of theouter pipe section 11.

As shown in FIG. 5, the outer wall portion of the outer pipe section 11is indented above the plane of the ring 40 at points preferably incircumferential alignment with the extensions 41 to form projections 50having inner arc portions 51 positioned in substantially the same radialposition as the vertical extending portions 21 of the projections 20.Thereby, the arc portions 51 function to loosely hold the lower end ofthe intermediate pipe section 12 in a concentric relationship betweenthe pipe sections 11 and 13. The lower end of the pipe section 12 restsupon the supporting structure formed by the extensions 41 on the spacerring 40.

An annular projection 60 is formed around the outer periphery of theinner pipe section 13, preferably by 7 being indented therein, adjacentits lower end but a spaced distan ce therefrom. The annular projectionlies in a planesubstantially perpendicular to the longitudinal axis ofthe pipe section 13 and is longitudinally positioned from the lower endof the inner pipe section 11 to rest against the inside surface of thespacer ring 40 when the flared end 31 of the inner pipe section isfitted around the inwardly extendingannular flange 30 of the upperspacer ring 22. The lower end 32 of the inner pipe section 11 extendsdownwardly from the annular projection 60 formed therearound and isdimensioned for insertion into the male end 14 of an adjacent pipeassembly 10, as shownin FIG. 4.

Although I have herein shown and described the invention in what I haveconceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of myinvention.

What is claimed is:

1. A pipe assembly for forming a chimney, comprismg:

substantially cylindrical outer, intermediate and inner pipe sections,and pipe sections being positioned concentrically one within the otherand dimensioned to define spaced apart walls;

a group of projections formed on the inner peripheral surface of saidouter pipe section adjacent each end thereof for maintaining saidintermediate pipe section concentrically positioned within said outerpipe section, the length of said intermediate pipe section being lessthan the length of said outer pipe section but at least as long as thelongitudinal distance between said groups of projections;

first and second spacer rings, each of said spacer rings having an outerdiameter a predetermined amount smaller than the inner diameter of saidintermediate pipe section and an inner diameter larger than the outerdiameter of said inner pipe section;

support structure secured between said outer pipe section and saidspacer rings mounting said first and second spacer rings concentricallywithin said outer pipe section at opposite ends thereof, said supportstructure positioned to hold the ends of said intermediate pipe sectionlongitudinally within the ends of said outer pipe section in alongitudinal position in which portions of the outer periphery surfaceof said intermediate pipe section are positioned within each of saidgroups of projections and hence are held concentrically positionedthereby; and

cooperating structure means formed on said spacer rings and inner pipesection for supporting said inner pipe section within said intermediatepipe section, said structure means being operable to hold, said innerpipe section in a substantially fixed longitudinal position concentricwith said outer pipe section.

2. The inventiondefined in claim 1 wherein each of said groups ofprojections are formed by making circumferentially spaced apartindentations in the outer peripheral surface of said outer pipe section.

3. The invention defined in claim 1 wherein each of said groups ofprojections is comprised of more than two projections, the projectionsin each of said groups being spaced apart circumferentiallysubstantially equally.

4. The invention defined in claim 3 wherein said projections in each ofsaid groups define a common plane substantially perpendicular to thelongitudinal axis of said outer pipe section.

5. The invention defined in claim 1 wherein said support structurecomprises extensions formed as an integral part of said spacer rings,said extensions corresponding in number to said projections and eachbeing rigidly secured to said outer pipe section in radial alignmentwith one of said projections.

6. The invention defined in claim 5 wherein each of said spacer ringsand said extensions formed integral therewith are planar and define acommon plane, said extensions being secured to said outer pipe sectionto extend substantially perpendicular to the axis thereof whereby saidspacer rings are positioned in a plane substantially perpendicular tothe axis of said outer pipe section.

7. The invention defined in claim 1, wherein said structure means forsupporting said inner pipe section within said intermediate pipe sectioncomprises:

an inwardly extending annular flange portion formed on said first spacerring, said annular flange portion being concentrically positioned withrespect to said outer pipe section;

an outward annular flare formed on the end of said inner pipe sectionadjacent said first spacer ring, said outward flare being dimensioned tomate with said annular flange portion by fitting thereover; and

an annular projection formed around the outer periphery of said innerpipe section adjacent its other end but a spaced distance therefrom,said annular projection being longitudinally positioned to rest againstthe inside surface of said second spacer ring whenever the flared end ofsaid inner pipe section is fitted around the inwardly extending annularflange portion of said first spacer ring, the end portion of said innerpipe section extending outwardly from said annular projection formedtherearound being for insertion into the annular flange portion of thefirst spacer ring of a second of said pipe assemblies at the time ofassembling two of said pipe assemblies together.

8. The invention defined in claim 7 wherein said outer pipe section hasformed on its opposite ends interlocking male and female structure meansfor joining one of said pipe assemblies with another.

9. The invention defined in claim 8, wherein:

said support structure comprises extensions formed as an integral partof said spacer rings, said extensions corresponding in number to saidprojections and each being rigidly secured to said outer pipe section inradial alignment with one of said projections;

each of said spacer rings and said extensions formed integral therewithare planar and define a common plane, said extensions being secured tosaid outer pipe section to extend substantially perpendicular to theaxis thereof whereby said spacer rings are positioned in a planesubstantially perpendicular to the axis of said outer pipe section; and

each of said groups of projections are formed by makingcircumferentially spaced apart indentations in the outer peripheralsurface of said outer pipe section, each of said groups of projectionsbeing comprised of more than two projections. the

projections in each of said groups being spaced apart circumferentiallysubstantially equally, said projections in each of said groups defininga common plane substantially perpendicular to the longitudinal axis ofsaid outer pipe section.

10. The invention defined in claim 1 wherein said outer pipe section hassupporting on its opposite ends interlocking male and female structuremeans for joining one of said pipe assemblies with another.

11. The invention defined in claim 1 wherein said pipe sections, saidprojections, said spacer rings, said support structure means and saidcooperating structure means are dimensioned with respect to each otherto accommodate a limited amount of relative movement due to settling,thermal expansion and contraction, or the like, without damage.

12. In a prefabricated pipe assembly for use in forming a chimney havingouter, intermediate, and inner pipe sections defining spaced apartwalls, the improvement in combination therewith of:

first and second longitudinally spaced apart groups of projection meansformed on the inner periphery of said outer pipe section for maintainingsaid intermediate pipe section concentrically positioned therein;

a pair of spacer rings each having an outer diameter a predeterminedamount smaller than the inner diameter of said intermediate pipe sectionand an inner diameter larger than the outer diameter of said inner pipesection;

support structure secured between said outer pipe section and saidspacer rings mounting said first and second spacer rings concentricallywithin said outer pipe section at opposite ends thereof, said supportstructure positioned to hold the ends of said intermediate pipe sectionlongitudinally within the ends of said outer pipe section in alongitudinal position in which portions of the outer peripheral surfaceof said intermediate pipe section are positioned within each of saidgroups of projection means and hence are held concentrically positionedthereby; and

cooperating structure means formed on said spacer rings and inner pipesection for supportin said inner pipe section within said intermediatepipe section. said structure means being operable to hold said andfemale interlocking structure means are formed on opposite ends of saidpipe assembly for joining one of said pipe assemblies with another.

1. A pipe assembly for forming a chimney, comprising: substantially cylindrical outer, intermediate and inner pipe sections, and pipe sections being positioned concentrically one within the other and dimensioned to define spaced apart walls; a group of projections formed on the inner peripheral surface of said outer pipe section adjacent each end thereof for maintaining said intermediate pipe section concentrically positioned within said outer pipe section, the length of said intermediate pipe section being less than the length of said outer pipe section but at least as long as the longitudinal distance between said groups of projections; first and second spacer rings, each of said spacer rings having an outer diameter a predetermined amount smaller than the inner diameter of said intermediate pipe section and an inner diameter larger than the outer diameter of said inner pipe section; support structure secured between said outer pipe section and said spacer rings mounting said first and second spacer rings concentrically within said outer pipe section at opposite ends thereof, said support structure positioned to hold the ends of said intermediate pipe section longitudinally within the ends of said outer pipe section in a longitudinal position in which portions of the outer periphery surface of said intermediate pipe section are positioned within each of said groups of projections and hence are held concentrically positioned thereby; and cooperating structure means formed on said spacer rings and inner pipe section for supporting said inner pipe section within said intermediate pipe section, said structure means being operable to hold said inner pipe section in a substantially fixed longitudinal position concentric with said outer pipe section.
 2. The invention defined in claim 1 wherein each of said groups of projections are formed by making circumferentially spaced apart indentations in the outer peripheral surface of said outer pipe section.
 3. The invention defined in claim 1 wherein each of said groups of projections is comprised of more than two projections, the projections in each of said groups being spaced apart circumferentially substantially equally.
 4. The invention defined in claim 3 wherein said projections in each of said groups define a common plane substantially perpendicular to the longitudinal axis of said outer pipe section.
 5. The invention defined in claim 1 wherein said support structure comprises extensions formed as an integral part of said spacer rings, said extensions corresponding in number to said projections and each being rigidly secured to said outer pipe section in radial alignment with one of said projections.
 6. The invention defined in claim 5 wherein each of said spacer rings and said extensions formed integral therewith are planar and define a common plane, said extensions being secured to said outer pipe section to extend substantially perpendicular to the axis thereof whereby said spacer rings are positioned in a plane substantially perpendicular to the axis of said outer pipe section.
 7. The invention defined in claim 1, wherein said structure means for supporting said inner pipe section within said intermediate pipe section comprises: an inwardly extending annular flange portion formed on said first spacer ring, said annular flange portion being concentrically positioned with respect to said outer pipe section; an outward annular flare formed on the end of said inner pipe section adjacent said first spacer ring, said outward flare being dimensioned to mate with said annular flange portion by fitting thereover; and an annular projection formed around the outer periphery of said inner pipe section adjacent its other end but a spaced distance therefrom, said annular projection being longitudinally positioned to rest against the inside surface of said second spacer ring whenever the flared end of said inner pipe section is fitted around the inwardly extending annular flange portion of said first spacer ring, the end portion of said inner pipe section extending outwardly from said annular projection formed therearound being for insertion into the annular flange portion of the first spacer ring of a second of said pipe assemblies at the time of assembling two of said pipe assemblies together.
 8. The invention defined in claim 7 wherein said outer pipe section has formed on its opposite ends interlocking male and female structure means for joining one of said pipe assemblies with another.
 9. The invention defined in claim 8, wherein: said support structure comprises extensions formed as an integral part of said spacer rings, said extensions corresponding in number to said projections and each being rigidly secured to said outer pipe section in radial alignment with one of said projections; each of said spacer rings and said extensions formed integral therewith are planar and define a common plane, said extensions being secured to said outer pipe section to extend substantially perpendicular to the axis thereof whereby said spacer rings are positioned in a plane substantially perpendicular to the axis of said outer pipe section; and each of said groups of projections are formed by making circumferentially spaced apart indentations in the outer peripheral surface of said outer pipe section, each of said groups of projections being comprised of more than two projections, the projections in each of said groups being spaced apart circumferentially substantially equally, said projections in each of said groups defining a common plane substantially perpendicular to the longitudinal axis of said outer pipe section.
 10. The invention defined in claim 1 wherein said outer pipe section has supporting on its opposite ends interlocking male and female structure means for joining one of said pipe assemblies with another.
 11. The invention defined in claim 1 wherein said pipe sections, said projections, said spacer rings, said support structure means and said cooperating structure means are dimensioned with respect to each other to accommodate a limited amount of relative movement due to settling, thermal expansion and contraction, or the like, without damage.
 12. In a prefabricated pipe assembly for use in forming a chimney having outer, intermediate, and inner pipe sections defining spaced apart walls, the improvement in combination therewith of: first and second longitudinally spaced apart groups of projection means formed on the inner periphery of said outer pipe section for maintaining said intermediate pipe section concentrically positioned therein; a pair of spAcer rings each having an outer diameter a predetermined amount smaller than the inner diameter of said intermediate pipe section and an inner diameter larger than the outer diameter of said inner pipe section; support structure secured between said outer pipe section and said spacer rings mounting said first and second spacer rings concentrically within said outer pipe section at opposite ends thereof, said support structure positioned to hold the ends of said intermediate pipe section longitudinally within the ends of said outer pipe section in a longitudinal position in which portions of the outer peripheral surface of said intermediate pipe section are positioned within each of said groups of projection means and hence are held concentrically positioned thereby; and cooperating structure means formed on said spacer rings and inner pipe section for supportin said inner pipe section within said intermediate pipe section, said structure means being operable to hold said inner pipe section in a substantially fixed longitudinal position concentric with said outer pipe section.
 13. The invention defined in claim 12 wherein male and female interlocking structure means are formed on opposite ends of said pipe assembly for joining one of said pipe assemblies with another. 